A resolver decoding circuit

Abstract

This application discloses a rotary transformer decoding circuit, which includes a decoding control chip, an excitation signal conditioning circuit, and two feedback signal conditioning circuits. The excitation signal conditioning circuit includes a first current transformer, a first transient voltage suppression diode, and two first filter components. The two feedback signal conditioning circuits respectively connect a sine wave signal interface to the decoding control chip and a cosine wave signal interface to the decoding control chip. Each feedback signal conditioning circuit includes a second current transformer, a second transient voltage suppression diode, and a second filter component. This rotary transformer decoding circuit can reduce the influence of external interference on the decoding result, enabling the decoding circuit to accurately resolve data in complex working environments, and can protect the decoding control chip from damage.

Description

Technical Field

[0001] This application relates to the field of decoding circuit technology, and in particular to a rotary transformer decoding circuit. Background Technology

[0002] A rotary transformer is a precision electromechanical component used for positioning and speed measurement. Its output electrical signal has a specific functional relationship with the rotor angle, and it is commonly used as a position and speed feedback sensor for synchronous motors. Its characteristics, including resistance to high temperatures, extreme cold, humidity, high speeds, high vibrations, and sufficiently high precision, make it irreplaceable in many applications and it is widely used in military, aerospace, aviation, and marine fields.

[0003] The resolver decoding circuit is the core system that converts the sine and cosine signals output by the resolver into digital angle information. Current resolver decoding circuits are susceptible to the combined effects of sensor cable length and electromagnetic interference, which can cause resolver signal parsing errors and damage to the decoding control chip in complex working environments. Utility Model Content

[0004] This application provides a rotary transformer decoding circuit, which solves the technical problem that existing rotary transformer decoding circuits are susceptible to the combined effects of sensor cable length and electromagnetic interference.

[0005] This application provides a rotary transformer decoding circuit, which includes: a decoding control chip; an excitation signal conditioning circuit, the excitation signal conditioning circuit including a first current transformer, a first transient voltage suppression diode, and two first filter components; the two ends of the first current transformer are respectively connected to the input terminals of the two first filter components and a reference signal interface, the output terminals of the two first filter components are connected to the decoding control chip, one end of the first transient voltage suppression diode is connected to the input terminal of the two first filter components, and the other end of the first transient voltage suppression diode is grounded; and two feedback signal conditioning circuits, the two feedback signal conditioning circuits... The feedback signal conditioning circuit connects the sine wave signal interface to the decoding control chip and the cosine wave signal interface to the decoding control chip, respectively. Each feedback signal conditioning circuit includes a second current transformer, a second transient voltage suppression diode, and a second filter component. One end of the second current transformer is connected to the sine wave signal interface or the cosine wave signal interface, and the other end of the second current transformer is connected to the input terminal of the second filter component. The output terminal of the second filter component is connected to the decoding control chip. One end of the second transient voltage suppression diode is connected to the input terminal of the second filter component, and the other end of the second transient voltage suppression diode is grounded.

[0006] In one possible implementation, the first filtering component includes a voltage follower, a first first-order low-pass filter, and a feedback-type Butterworth second-order low-pass filter connected in sequence; the input terminal of the voltage follower is connected to the first current transformer, and the output terminal of the feedback-type Butterworth second-order low-pass filter is connected to the decoding control chip; wherein, the input terminal of the first transient voltage suppression diode is connected to the input terminal of the voltage follower.

[0007] In one possible implementation, the second filtering component includes a differential common-mode filter circuit and a second first-order low-pass filter connected in sequence; the input terminal of the differential common-mode filter circuit is connected to the second mutual inductor, and the output terminal of the second first-order low-pass filter is connected to the decoding control chip.

[0008] This application provides a rotary transformer decoding circuit, which includes a decoding control chip, an excitation signal conditioning circuit, and two feedback signal conditioning circuits. The excitation signal conditioning circuit includes a first current transformer, a first transient voltage suppression diode, and two first filter components. The feedback signal conditioning circuit includes a second current transformer, a second transient voltage suppression diode, and a second filter component. The first and second current transformers can reduce the impact of strong external interference on the decoding process and results of the decoding control chip. The first and second transient voltage suppression diodes can clamp overvoltage signals, preventing abnormal high voltage from damaging the decoding control chip, the first filter component, and the second filter component. The first and second filter components can filter out interference noise in the signal, reducing the possibility of signal parsing errors or damage to the decoding control chip. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments of this application or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 A schematic diagram of a rotary transformer decoding circuit provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the first filtering component provided in an embodiment of this application; Figure 3 This is a schematic diagram of the structure of the second filtering component provided in an embodiment of this application.

[0011] Figure reference numerals: 1-Decoding control chip; 2-Excitation signal conditioning circuit; 21-First current transformer; 22-First transient voltage suppression diode; 23-First filter component; 231-Voltage follower; 2311-First resistor; 2312-First operational amplifier; 232-First first-order low-pass filter; 2321-Second resistor; 2322-First capacitor; 233-Feedback type Butterworth second-order low-pass filter; 2331-Second operational amplifier; 2332-Third resistor; 2333-Second capacitor; 2334-Fourth resistor ; 2335 - Fifth resistor; 2336 - Third capacitor; 3 - Feedback signal conditioning circuit; 31 - Second current transformer; 32 - Second transient voltage suppression diode; 33 - Second filter component; 331 - Differential common-mode filter circuit; 3311 - Fully differential operational amplifier; 3312 - Sixth resistor; 3313 - Seventh resistor; 3314 - Eighth resistor; 3315 - Ninth resistor; 332 - Second first-order low-pass filter; 3321 - Tenth resistor; 3322 - Fourth capacitor; 3323 - Eleventh resistor; 3324 - Fifth capacitor. Detailed Implementation

[0012] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0013] like Figure 1 As shown in the figure, this application provides a rotary transformer decoding circuit, which includes a decoding control chip 1, an excitation signal conditioning circuit 2, and two feedback signal conditioning circuits 3.

[0014] The excitation signal conditioning circuit 2 includes a first current transformer 21, a first transient voltage suppression diode 22, and two first filter components 23. The two ends of the first current transformer 21 are respectively connected to the input terminals of the two first filter components 23 and the reference signal interface. The output terminals of the two first filter components 23 are connected to the decoding control chip 1. One end of the first transient voltage suppression diode 22 is connected to the input terminal of the two first filter components 23, and the other end of the first transient voltage suppression diode 22 is grounded.

[0015] When the first transformer 21 is working, the signal input from the reference signal interface is transmitted to the secondary coil of the first transformer 21 through the magnetic coupling between the primary coil and the secondary coil, so as to avoid the external strong interference signal affecting the conditioning process of the excitation signal conditioning circuit 2.

[0016] The first transient voltage suppression diode 22 can clamp overvoltage signals to protect the first filter component 23 and the decoding control chip 1, so that the first filter component 23 and the decoding control chip 1 are protected from damage by abnormal voltage on the circuit board.

[0017] The first filter component 23 is used to filter out interference noise in the excitation signal, avoid direct coupling between the decoding control chip 1 and the excitation signal, and reduce the possibility of signal parsing errors or damage to the decoding control chip 1.

[0018] Two feedback signal conditioning circuits 3 connect the sine wave signal interface and the decoding control chip 1, respectively, and the cosine wave signal interface and the decoding control chip 1. For example, in... Figure 1 In the middle, the upper feedback signal conditioning circuit 3 is connected to the sine signal interface and the decoding control chip 1, and the lower feedback signal conditioning circuit 3 is connected to the cosine signal interface and the decoding control chip 1. Each feedback signal conditioning circuit 3 includes a second current transformer 31, a second transient voltage suppression diode 32, and a second filter component 33.

[0019] One end of the second current transformer 31 is connected to the sine signal interface or the cosine signal interface, and the other end of the second current transformer 31 is connected to the input terminal of the second filter component 33. The output terminal of the second filter component 33 is connected to the decoding control chip 1. One end of the second transient voltage suppression diode 32 is connected to the input terminal of the second filter component 33, and the other end of the second transient voltage suppression diode 32 is grounded.

[0020] When the second transformer 31 is working, the sine and cosine signals of the rotary transformer reach the secondary coil through the magnetic coupling of the primary and secondary coils, so as to isolate strong external interference and avoid the strong external interference from affecting the feedback signal conditioning circuit 3.

[0021] The second transient voltage suppression diode 32 can clamp overvoltage signals to protect the second filter component 33 and the decoding control chip 1, so that the second filter component 33 and the decoding control chip 1 are protected from damage by abnormal voltage on the circuit board.

[0022] The second filter component 33 can filter out interference noise in sine and cosine signals, avoid direct coupling between the decoding control chip 1 and the sine / cosine signals, and reduce the possibility of signal parsing errors or damage to the decoding control chip 1.

[0023] like Figure 1 and Figure 2As shown in this embodiment, the first filtering component 23 includes a voltage follower 231, a first-order low-pass filter 232, and a feedback-type Butterworth second-order low-pass filter 233 connected in sequence. The input terminal of the voltage follower 231 is connected to the first current transformer 21, and the output terminal of the feedback-type Butterworth second-order low-pass filter 233 is connected to the decoding control chip 1. The input terminal of the first transient voltage suppression diode 22 is connected to the input terminal of the voltage follower 231.

[0024] Specifically, refer to Figure 2 The voltage follower 231 includes a first resistor 2311 and a first operational amplifier 2312. The first first-order low-pass filter 232 includes a first capacitor 2322 and a second resistor 2321. The feedback-type Butterworth second-order low-pass filter 233 includes a second operational amplifier 2331, a second capacitor 2333, a fourth resistor 2334, a fifth resistor 2335, a third resistor 2332, and a third capacitor 2336. The two ends of the first resistor 2311 are connected to the output and inverting input of the first operational amplifier 2312, respectively; the output of the first operational amplifier 2312 is connected to the first current transformer 21; one end of the first capacitor 2322 is connected to the non-inverting input of the first operational amplifier 2312, and the other end of the first capacitor 2322 is grounded; one end of the second resistor 2321 is connected to the non-inverting input of the first operational amplifier 2312, and the other end of the second resistor 2321 is connected to the output of the second operational amplifier 2331; the two ends of the second capacitor 2333 are connected to the output and inverting input of the second operational amplifier 2331, respectively; the second operational amplifier... The non-inverting input of the second operational amplifier 2331 is grounded; one end of the fourth resistor 2334 is connected to the inverting input of the second operational amplifier 2331, and the other end of the fourth resistor 2334 is connected to one end of the fifth resistor 2335; the other end of the fifth resistor 2335 is connected to the decoding control chip 1; one end of the third capacitor 2336 is connected to the end of the fourth resistor 2334 furthest from the second operational amplifier 2331, and the other end of the third capacitor 2336 is grounded; one end of the third resistor 2332 is connected to the end of the fourth resistor 2334 furthest from the second operational amplifier 2331, and the other end of the third resistor 2332 is connected to the output of the second operational amplifier 2331.

[0025] The voltage follower 231 can buffer and drive the connection between the first current transformer 21 and the first first-order low-pass filter 232. The first-order low-pass filter 232 and the feedback-type Butterworth second-order low-pass filter 233 can filter out high-frequency noise in the signal and improve signal quality.

[0026] Furthermore, in the feedback-type Butterworth second-order low-pass filter 233, Figure 2In the structure shown, the signal amplification ratio is adjusted by changing the third resistor 2332 and the fifth resistor 2335, thereby enabling the first filter component 23 to adapt to rotary transformers of different specifications.

[0027] like Figure 1 and Figure 3 As shown in this embodiment, the second filtering component 33 includes a differential common-mode filter circuit 331 and a second first-order low-pass filter 332 connected in sequence. The input terminal of the differential common-mode filter circuit 331 is connected to the second current transformer 31, and the output terminal of the second first-order low-pass filter 332 is connected to the decoding control chip 1.

[0028] Specifically, refer to Figure 3 The differential common-mode filter circuit 331 includes a fully differential operational amplifier 3311, a sixth resistor 3312, a seventh resistor 3313, an eighth resistor 3314, and a ninth resistor 3315; the second first-order low-pass filter 332 includes a tenth resistor 3321, an eleventh resistor 3323, a fourth capacitor 3322, and a fifth capacitor 3324. The two ends of the sixth resistor 3312 are connected to the positive output and negative input of the fully differential operational amplifier 3311, respectively; the two ends of the seventh resistor 3313 are connected to the negative input of the fully differential operational amplifier 3311 and the second current transformer 31, respectively; the two ends of the eighth resistor 3314 are connected to the negative output and positive input of the fully differential operational amplifier 3311, respectively; the two ends of the ninth resistor 3315 are connected to the positive input of the fully differential operational amplifier 3311 and the second current transformer 31, respectively; the two ends of the tenth resistor 3321 are connected to the positive output and negative input of the fully differential operational amplifier 3311, respectively; the two ends of the tenth resistor 3321 are connected to the positive output and negative input of the fully differential operational amplifier 3311, respectively; the two ends of the ninth resistor 3315 are connected to the positive input of the fully differential operational amplifier 3311 and the second current transformer 3 ... The eleventh resistor 3323 is connected to the positive output terminal of the fully differential operational amplifier 3311 and the decoding control chip 1, respectively; one end of the fourth capacitor 3322 is connected to the end of the tenth resistor 3321 connected to the decoding control chip 1, and the other end of the fourth capacitor 3322 is grounded; one end of the fifth capacitor 3324 is connected to the end of the eleventh resistor 3323 connected to the decoding control chip 1, and the other end of the fifth capacitor 3324 is grounded.

[0029] When the second filtering component 33 is working, the differential common-mode filter circuit 331 can filter out differential-mode interference in the input signal, and the second first-order low-pass filter 332 can filter out high-frequency differential-mode interference in the input signal. Under the combined action of the differential common-mode filter circuit 331 and the second first-order low-pass filter 332, the signal quality is greatly improved, enabling the sine and cosine signals to be effectively recognized by the decoding control chip 1, reducing the difficulty of decoding algorithms or hardware decoding, and shortening the engineering development and debugging cycle.

[0030] Furthermore, in the differential common-mode filter circuit 331, for Figure 3With the structure shown, by changing the sixth resistor 3312, the seventh resistor 3313, the eighth resistor 3314 and the ninth resistor 3315, the signal amplification ratio can be changed, thereby enabling the second filter component 33 to adapt to rotary transformers of different specifications.

[0031] The various embodiments in this specification are described in a progressive manner. For the same or similar parts between the various embodiments, please refer to each other. Each embodiment focuses on describing the differences from other embodiments.

[0032] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of this application.

Claims

1. A rotary transformer decoding circuit, characterized in that, include: Decoding control chip; An excitation signal conditioning circuit, comprising a first current transformer, a first transient voltage suppression diode, and two first filter components; The two ends of the first current transformer are respectively connected to the input terminals of the two first filter components and the reference signal interface. The output terminals of the two first filter components are connected to the decoding control chip. One end of the first transient voltage suppression diode is connected to the input terminals of the two first filter components, and the other end of the first transient voltage suppression diode is grounded. Two feedback signal conditioning circuits are provided, which respectively connect the sine wave signal interface to the decoding control chip and the cosine wave signal interface to the decoding control chip; wherein each feedback signal conditioning circuit includes a second current transformer, a second transient voltage suppression diode and a second filter component. One end of the second current transformer is connected to the sine signal interface or the cosine signal interface, the other end of the second current transformer is connected to the input terminal of the second filter component, the output terminal of the second filter component is connected to the decoding control chip, one end of the second transient voltage suppression diode is connected to the input terminal of the second filter component, and the other end of the second transient voltage suppression diode is grounded.

2. The rotary transformer decoding circuit according to claim 1, characterized in that, The first filtering component includes a voltage follower, a first-order low-pass filter, and a feedback-type Butterworth second-order low-pass filter connected in sequence. The input terminal of the voltage follower is connected to the first current transformer, and the output terminal of the feedback type Butterworth second-order low-pass filter is connected to the decoding control chip. The input terminal of the first transient voltage suppression diode is connected to the input terminal of the voltage follower.

3. The rotary transformer decoding circuit according to claim 1, characterized in that, The second filtering component includes a differential common-mode filter circuit and a second first-order low-pass filter connected in sequence; The input terminal of the differential common-mode filter circuit is connected to the second mutual inductor, and the output terminal of the second first-order low-pass filter is connected to the decoding control chip.

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